The present invention relates to sense amplifiers and, more particularly, relates to sense amplifiers that compensate for variations and mismatches in a memory circuit.
As information technology progresses at an unprecedented pace, the need for information storage increases proportionately. Accordingly, the non volatile information in stationary or portable communication demands higher capability and capacity storage. One approach to increasing the amount of storage is by decreasing physical dimensions of the stored bit (e.g., memory cell) to smaller dimensions such as nanocell technology. Another approach is to increase the storage density per bit. The second approach is known as digital multilevel nonvolatile storage technology. A sense amplifier reads the content of a memory cell by comparison to reference levels. As more bits are stored in a multilevel memory cell, the voltage separation of reference levels decreases. Systematic and random variation and mismatch in a sense amplifier may change data or reference levels to cause erroneous detection of the content of a memory cell.